Currently injections are the only method to deliver insulin. Pfizer Inc. and Inhale Therapeutic Systems have developed a dry powder insulin formulation and aerosol delivery device, that safely delivers a rapid acting insulin, by forming a cloud that patients can draw into their lungs where the insulin is absorbed. Since inflammation can reduce the tolerance and bioavailability of inhaled medications, this study will measure changes in tolerance and bioavailability of inhaled insulin during rhinoviral infection.